Stabilized approximate inverse preconditioning based on A-orthogonalization process for parallel finite element analysis

Improved Stabilized Approximate Inverse (ISAINV) based on A-orthogonalization process is known as an effective preconditioning technique for the conjugate gradient (CG) method to solve highly ill-conditioned linear systems. This research aims to accelerate the convergence of the finite element analysis of shell structures by preserving the sparsity in the preconditioning matrix and by parallelizing the localized process of ISAINV preconditioning. In the numerical results, the proposed ISAINV preconditioner shows better convergence and faster computational time than the conventional preconditioning.